Harris Science Academy East London (HSAEL), formerly known as East London Science School (ELSS), is a coeducational secondary free school with specialist school status in science and language in Stratford, Bromley and Bow, in the London boroughs of Newham and Tower Hamlets. It was founded on Three Mills Island in its first temporary and current main site, the Clock Mill, by its first principal, David Perks, in 2013. The school originally planned to move to its permanent site two years after its opening, however this has yet to occur. The new building is being built by Berkeley Homes as part of its Twelvetrees Park development project (formerly Stephenson Street) and is expected to be complete sometime in 2022.